The present invention relates to a regenerator for glass melting tanks, for storing waste heat from combustion cycles and for emitting the stored heat to oxidation gases supplied from the outside, having a gas-permeable chamber lattice made up of regenerative chambers having a chamber lining made of fire-resistant stones held together by lateral wall elements, having an upper limiting surface and a lower limiting surface that are situated at a distance from a chamber cover and a chamber floor, a cover region being situated over the chamber lattice for the combustion gases entering into the chamber lattice and for the oxidation gases exiting from the chamber lattice, the cover region being connected to the glass melting tank via a burner port, the vertical cross-section of the burner port being situated at least partly underneath the upper limiting surface of the chamber lattice, opening into the cover region, and a further cover segment being connected to the chamber cover, which further segment upwardly terminates the cover region and is limited by a downward-extending terminating wall that is connected to the burner throat and that forms a flow duct together with the wall element.
In the book by Wolfgang Trier, Glasschmelzöfen Konstruktion and Betriebsverhalten [Design and operating behavior of glass melting ovens], 1984, Springer-Verlag, pp. 35-46, it is described how, in the melting of glass for heat recuperation by means of heat regenerators, also referred to as regenerators or regenerative chambers, the waste heat can be made useful for pre-heating the combustion air. Gas-permeable lattice structures are situated in a vertical shaft or housing in the regenerative chambers, through which lattices exhaust gases or combustion gases from glass melting ovens flow in alternating fashion, and which emit a part of the stored heat to the oxidation gas after the periodic reversal of the flow direction, whereby the thermal efficiency of the entire installation can be significantly increased. Here, the laterally situated burner port of the melting tank is situated above the upper limiting surface of the lattice structure. Depending on the power rating of the melting oven, this results in significant constructive heights of the regenerators.
The dimensioning of the lattice structures is essentially determined by the overall power level of the glass melting tanks. As the constructive height of the regenerator, and the defined position of the glass melting tanks, increases, this requires either a deeper foundation or an increased surface requirement. Both of these entail significant disadvantages.
Therefore, U.S. Pat. No. 2,068,924 has already proposed to situate the burner port in a regenerator in such a way that it opens into the cover space underneath the chamber lattice. However, this means that a separating wall is required between the upper chamber lattice and the burner port, which wall is strongly thermally loaded from both sides and is constantly exposed to the corrosive exhaust gas of the melting tank. This holds in particular for the region of the upper layers of the fire-resistant stones of the regenerative chambers, which, when the firing is changed, are exposed to a significant thermal shock.